Re: [PATCH] net/gianfar: drop recycled skbs on MTU change

[Andy Fleming <afleming@gmail.com>]

On Mon, May 3, 2010 at 8:17 AM, Sebastian Andrzej Siewior
<sebastian@breakpoint.cc> wrote:
> From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
>
> The size for skb which is added to the recycled list is using the
> current descriptor size which is current MTU. gfar_new_skb() is also
> using this size. So after changing or alteast increasing the MTU all
> recycled skbs should be dropped.
>
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> ---
> I'm not 100% sure but it looks like it is wrong.
>
>  drivers/net/gianfar.c |    4 +++-
>  1 files changed, 3 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/net/gianfar.c b/drivers/net/gianfar.c
> index 5267c27..9093106 100644
> --- a/drivers/net/gianfar.c
> +++ b/drivers/net/gianfar.c
> @@ -2287,8 +2287,10 @@ static int gfar_change_mtu(struct net_device *dev, int new_mtu)
>
>        /* Only stop and start the controller if it isn't already
>         * stopped, and we changed something */
> -       if ((oldsize != tempsize) && (dev->flags & IFF_UP))
> +       if ((oldsize != tempsize) && (dev->flags & IFF_UP)) {
>                stop_gfar(dev);
> +               skb_queue_purge(&priv->rx_recycle);
> +       }


I think we should probably do this in free_skb_resources.  And remove
the call from gfar_close().

Andy